A programmable sub-surface aggregating metallization structure ("PSAM")
includes an ion conductor such as a chalcogenide-glass which includes
metal ions and at least two electrodes disposed at opposing surfaces of
the ion conductor. Preferably, the ion conductor includes a chalcogenide
material with Group IB or Group IIB metals. One of two electrodes is
preferably configured as a cathode and the other as an anode. When a
voltage is applied between the anode and cathode, a metal dendrite grows
from the cathode through the ion conductor towards the anode. The growth
rate of the dendrite may be stopped by removing the voltage or the
dendrite may be retracted back towards the cathode by reversing the
voltage polarity at the anode and cathode.